This invention relates to toner processes, and more specifically, to aggregation and coalescence processes. More specifically, the present invention relates in embodiments to methods for the preparation of toner compositions by a chemical process, such as emulsion/aggregation/coalescence wherein latex particles are aggregated with a wax, a crosslinked gel with, for example, from about 20 to about 55 percent gel as measured gravimetrically, colorants, a magnetite and colloidal silica in the presence of a coagulant like a polymetal halide, or alternatively a mixture of coagulants or flocculating agents, thereafter stabilizing the aggregates with a solution of an alkali metal hydroxide like sodium hydroxide, and thereafter coalescing or fusing by heating the mixture above the resin Tg to provide toner size particles which when developed by an electrographic process generates documents suitable for magnetic image character recognition or MICR.
A number of advantages are associated with the present invention in embodiments thereof including, for example, excellent toner hot offset, for example above about 210° C., and more specifically, from about 210° C. to about 230° C.; a toner fusing latitude of from about 20° C. to about 35° C., wherein fusing latitude refers to a temperature in which, when a developed image is fused, evidences substantially no offset either to the substrate that the image is fused on, referred to as “Cold” offset or an offset on the fuser roll referred to as the “HOT” offset; a toner minimum fixing temperature of, for example, about 170° C. to about 195° C.; and extended photoreceptor life since the toner fusing temperature can be below about 195° C., such as from about 175° C. to about 190° C.; and also in embodiments a process that enables a means of identifying how a toner was fabricated by, for example, analyzing for aluminum and silica contents.